
    window.onload = async () => {
    const env = {
        serviceUrl: "https://vjmap.com/server/api/v1",
        accessToken: "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJJRCI6MiwiVXNlcm5hbWUiOiJhZG1pbjEiLCJOaWNrTmFtZSI6ImFkbWluMSIsIkF1dGhvcml0eUlkIjoiYWRtaW4iLCJCdWZmZXJUaW1lIjo4NjQwMCwiZXhwIjo0ODEzMjY3NjM3LCJpc3MiOiJ2am1hcCIsIm5iZiI6MTY1OTY2NjYzN30.cDXCH2ElTzU2sQU36SNHWoTYTAc4wEkVIXmBAIzWh6M",
        exampleMapId: "sys_zp",
        assetsPath: "../../assets/",
        ...__env__ // 如果您已私有化部署，需要连接已部署的服务器地址和token，请打开js/env.js,修改里面的参数
    };
    try {
        // 在线效果查看地址: https://vjmap.com/map3d/demo/#/demo/map/threejs/200threeWebgltexture3dpartialupdate
        // --texture3d_partialupdate--
        // 下面代码参考threejs官方示例改写 https://threejs.org/examples/#webgl_texture3d_partialupdate
        let svc = new vjmap3d.Service(env.serviceUrl, env.accessToken);
        let app = new vjmap3d.App(svc, {
            container: "map", // 容器id
            scene: {
                defaultLights: false
            },
            camera: {
                fov: 60,
                near: 0.1,
                far: 100,
                position: [ 0, 0, 1.5]
            }
        })
        let scene = app.scene, camera = app.camera, renderer = app.renderer;
        
        
        const INITIAL_CLOUD_SIZE = 128;
        
        let mesh;
        let prevTime = performance.now();
        let cloudTexture = null;
        
        init();
        
        function generateCloudTexture( size, scaleFactor = 1.0 ) {
        
            const data = new Uint8Array( size * size * size );
            const scale = scaleFactor * 10.0 / size;
        
            let i = 0;
            const perlin = new ImprovedNoise();
            const vector = new THREE.Vector3();
        
            for ( let z = 0; z < size; z ++ ) {
        
                for ( let y = 0; y < size; y ++ ) {
        
                    for ( let x = 0; x < size; x ++ ) {
        
                        const dist = vector.set( x, y, z ).subScalar( size / 2 ).divideScalar( size ).length();
                        const fadingFactor = ( 1.0 - dist ) * ( 1.0 - dist );
                        data[ i ] = ( 128 + 128 * perlin.noise( x * scale / 1.5, y * scale, z * scale / 1.5 ) ) * fadingFactor;
        
                        i ++;
        
                    }
        
                }
        
            }
        
            return new THREE.Data3DTexture( data, size, size, size );
        
        }
        
        function init() {
        
        
            // Sky
        
            const canvas = document.createElement( 'canvas' );
            canvas.width = 1;
            canvas.height = 32;
        
            const context = canvas.getContext( '2d' );
            const gradient = context.createLinearGradient( 0, 0, 0, 32 );
            gradient.addColorStop( 0.0, '#014a84' );
            gradient.addColorStop( 0.5, '#0561a0' );
            gradient.addColorStop( 1.0, '#437ab6' );
            context.fillStyle = gradient;
            context.fillRect( 0, 0, 1, 32 );
        
            const skyMap = new THREE.CanvasTexture( canvas );
            skyMap.colorSpace = THREE.SRGBColorSpace;
        
            const sky = new THREE.Mesh(
                new THREE.SphereGeometry( 10 ),
                new THREE.MeshBasicMaterial( { map: skyMap, side: THREE.BackSide } )
            );
            scene.add( sky );
        
            // Texture
        
            const texture = new THREE.Data3DTexture(
                new Uint8Array( INITIAL_CLOUD_SIZE * INITIAL_CLOUD_SIZE * INITIAL_CLOUD_SIZE ).fill( 0 ),
                INITIAL_CLOUD_SIZE,
                INITIAL_CLOUD_SIZE,
                INITIAL_CLOUD_SIZE
            );
            texture.format = THREE.RedFormat;
            texture.minFilter = THREE.LinearFilter;
            texture.magFilter = THREE.LinearFilter;
            texture.unpackAlignment = 1;
            texture.needsUpdate = true;
        
            cloudTexture = texture;
        
            // Material
        
            const vertexShader = /* glsl */`
                in vec3 position;
        
                uniform mat4 modelMatrix;
                uniform mat4 modelViewMatrix;
                uniform mat4 projectionMatrix;
                uniform vec3 cameraPos;
        
                out vec3 vOrigin;
                out vec3 vDirection;
        
                void main() {
                    vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );
        
                    vOrigin = vec3( inverse( modelMatrix ) * vec4( cameraPos, 1.0 ) ).xyz;
                    vDirection = position - vOrigin;
        
                    gl_Position = projectionMatrix * mvPosition;
                }
            `;
        
            const fragmentShader = /* glsl */`
                precision highp float;
                precision highp sampler3D;
        
                uniform mat4 modelViewMatrix;
                uniform mat4 projectionMatrix;
        
                in vec3 vOrigin;
                in vec3 vDirection;
        
                out vec4 color;
        
                uniform vec3 base;
                uniform sampler3D map;
        
                uniform float threshold;
                uniform float range;
                uniform float opacity;
                uniform float steps;
                uniform float frame;
        
                uint wang_hash(uint seed)
                {
                        seed = (seed ^ 61u) ^ (seed >> 16u);
                        seed *= 9u;
                        seed = seed ^ (seed >> 4u);
                        seed *= 0x27d4eb2du;
                        seed = seed ^ (seed >> 15u);
                        return seed;
                }
        
                float randomFloat(inout uint seed)
                {
                        return float(wang_hash(seed)) / 4294967296.;
                }
        
                vec2 hitBox( vec3 orig, vec3 dir ) {
                    const vec3 box_min = vec3( - 0.5 );
                    const vec3 box_max = vec3( 0.5 );
                    vec3 inv_dir = 1.0 / dir;
                    vec3 tmin_tmp = ( box_min - orig ) * inv_dir;
                    vec3 tmax_tmp = ( box_max - orig ) * inv_dir;
                    vec3 tmin = min( tmin_tmp, tmax_tmp );
                    vec3 tmax = max( tmin_tmp, tmax_tmp );
                    float t0 = max( tmin.x, max( tmin.y, tmin.z ) );
                    float t1 = min( tmax.x, min( tmax.y, tmax.z ) );
                    return vec2( t0, t1 );
                }
        
                float sample1( vec3 p ) {
                    return texture( map, p ).r;
                }
        
                float shading( vec3 coord ) {
                    float step = 0.01;
                    return sample1( coord + vec3( - step ) ) - sample1( coord + vec3( step ) );
                }
        
                vec4 linearToSRGB( in vec4 value ) {
                    return vec4( mix( pow( value.rgb, vec3( 0.41666 ) ) * 1.055 - vec3( 0.055 ), value.rgb * 12.92, vec3( lessThanEqual( value.rgb, vec3( 0.0031308 ) ) ) ), value.a );
                }
        
                void main(){
                    vec3 rayDir = normalize( vDirection );
                    vec2 bounds = hitBox( vOrigin, rayDir );
        
                    if ( bounds.x > bounds.y ) discard;
        
                    bounds.x = max( bounds.x, 0.0 );
        
                    vec3 p = vOrigin + bounds.x * rayDir;
                    vec3 inc = 1.0 / abs( rayDir );
                    float delta = min( inc.x, min( inc.y, inc.z ) );
                    delta /= steps;
        
                    // Jitter
        
                    // Nice little seed from
                    // https://blog.demofox.org/2020/05/25/casual-shadertoy-path-tracing-1-basic-camera-diffuse-emissive/
                    uint seed = uint( gl_FragCoord.x ) * uint( 1973 ) + uint( gl_FragCoord.y ) * uint( 9277 ) + uint( frame ) * uint( 26699 );
                    vec3 size = vec3( textureSize( map, 0 ) );
                    float randNum = randomFloat( seed ) * 2.0 - 1.0;
                    p += rayDir * randNum * ( 1.0 / size );
        
                    //
        
                    vec4 ac = vec4( base, 0.0 );
        
                    for ( float t = bounds.x; t < bounds.y; t += delta ) {
        
                        float d = sample1( p + 0.5 );
        
                        d = smoothstep( threshold - range, threshold + range, d ) * opacity;
        
                        float col = shading( p + 0.5 ) * 3.0 + ( ( p.x + p.y ) * 0.25 ) + 0.2;
        
                        ac.rgb += ( 1.0 - ac.a ) * d * col;
        
                        ac.a += ( 1.0 - ac.a ) * d;
        
                        if ( ac.a >= 0.95 ) break;
        
                        p += rayDir * delta;
        
                    }
        
                    color = linearToSRGB( ac );
        
                    if ( color.a == 0.0 ) discard;
        
                }
            `;
        
            const geometry = new THREE.BoxGeometry( 1, 1, 1 );
            const material = new THREE.RawShaderMaterial( {
                glslVersion: THREE.GLSL3,
                uniforms: {
                    base: { value: new THREE.Color( 0x798aa0 ) },
                    map: { value: texture },
                    cameraPos: { value: new THREE.Vector3() },
                    threshold: { value: 0.25 },
                    opacity: { value: 0.25 },
                    range: { value: 0.1 },
                    steps: { value: 100 },
                    frame: { value: 0 }
                },
                vertexShader,
                fragmentShader,
                side: THREE.BackSide,
                transparent: true
            } );
        
            mesh = new THREE.Mesh( geometry, material );
            scene.add( mesh );
        
            //
        
            const parameters = {
                threshold: 0.25,
                opacity: 0.25,
                range: 0.1,
                steps: 100
            };
        
            function update() {
        
                material.uniforms.threshold.value = parameters.threshold;
                material.uniforms.opacity.value = parameters.opacity;
                material.uniforms.range.value = parameters.range;
                material.uniforms.steps.value = parameters.steps;
        
            }
        
            const gui = new GUI();
            gui.add( parameters, 'threshold', 0, 1, 0.01 ).onChange( update );
            gui.add( parameters, 'opacity', 0, 1, 0.01 ).onChange( update );
            gui.add( parameters, 'range', 0, 1, 0.01 ).onChange( update );
            gui.add( parameters, 'steps', 0, 200, 1 ).onChange( update );
        
            app.signal.onAppUpdate.add(animate)
        }
        
        let curr = 0;
        const countPerRow = 4;
        const countPerSlice = countPerRow * countPerRow;
        const sliceCount = 4;
        const totalCount = sliceCount * countPerSlice;
        const margins = 8;
        
        const perElementPaddedSize = ( INITIAL_CLOUD_SIZE - margins ) / countPerRow;
        const perElementSize = Math.floor( ( INITIAL_CLOUD_SIZE - 1 ) / countPerRow );
        
        function animate() {
        
            const time = performance.now();
            if ( time - prevTime > 1500.0 && curr < totalCount ) {
        
                const position = new THREE.Vector3(
                    Math.floor( curr % countPerRow ) * perElementSize + margins * 0.5,
                    ( Math.floor( ( ( curr % countPerSlice ) / countPerRow ) ) ) * perElementSize + margins * 0.5,
                    Math.floor( curr / countPerSlice ) * perElementSize + margins * 0.5
                ).floor();
        
                const maxDimension = perElementPaddedSize - 1;
                const box = new THREE.Box3( new THREE.Vector3( 0, 0, 0 ), new THREE.Vector3( maxDimension, maxDimension, maxDimension ) );
                const scaleFactor = ( Math.random() + 0.5 ) * 0.5;
                const source = generateCloudTexture( perElementPaddedSize, scaleFactor );
        
                renderer.copyTextureToTexture3D( source, cloudTexture, box, position );
        
                prevTime = time;
        
                curr ++;
        
            }
        
            mesh.material.uniforms.cameraPos.value.copy( camera.position );
            // mesh.rotation.y = - performance.now() / 7500;
        
            mesh.material.uniforms.frame.value ++;
        
        }
        
        
        
    }
    catch (e) {
        console.error(e);
    }
};